Unlike the older conventional vehicles, modern vehicles are equipped with various electronic devices for convenience and safety, and vehicles recently manufactured are mounted with many electronic parts. Particularly, an adaptive head lamp system controlling movement of vehicular head lamp is equipped with many electronic parts. The adaptive head lamp system moves a head lamp in response to a traveling direction and a traveling speed of a vehicle to allow an area illuminated by the head lamp to match the movement of the vehicle, to be more particularly, to match a driver's visual field (sight).
In order to change the movement of a head lamp in response to a traveling direction or a traveling speed of a vehicle while movement of the head lamp is being controlled, a faster response speed of a head lamp driving circuit is needed. Thus, reducing a charging/discharging time of a driving circuit of a head lamp is needed. Particularly, a certain automobile manufacturing company standardizes the charging/discharging time of a head lamp, such that a technology to control the charging/discharging time of a head lamp below a standard level is necessary.